/**
 * Copyright 2010 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package net.oauth.jsontoken.crypto;

/**
 * Enum of the signature algorithms supported by this package.
 */
public enum SignatureAlgorithm {
    HS256("SHA256"), HS1("SHA1"), RS256("SHA256"), RS1("SHA1");

    private final String hashAlg;

    private SignatureAlgorithm(String hashAlg) {
        this.hashAlg = hashAlg;
    }

    /**
     * What the signature algorithm is named in the "alg" parameter in a JSON Token's envelope.
     */
    public String getNameForJson() {
        return name();
    }

    /**
     * Returns the hash algorithm that should be used when hashing data. When large pieces
     * of data are to be included in a JSON Token's payload, it sometimes might make sense
     * to include the hash of the data instead. If an issuer wants to do that, they should
     * use this hash algorithm to hash the data.
     */
    public String getHashAlgorithm() {
        return hashAlg;
    }

    /**
     * Given the name of the algorithm in the envelope, returns the corresponding enum instance.
     */
    public static SignatureAlgorithm getFromJsonName(String name) {
        return SignatureAlgorithm.valueOf(name);
    }
}
